SEAWEEDS 



is paler and thinner than that of the widest ulva. 

 When young the sea lettuce is said to form an in- 

 flated bag, somewhat like a small toy balloon. Later, 

 this splits along the side and floats out, making a thin 

 leaf of but one layer of cells. This plant is not quite 

 so common as the larger one. 



The ulva is one of the seaweeds that lives but a 

 year. It is often found on the beach in the winter, 

 but it is most abundant during the spring and summer 

 months. 



FUCUS, OR ROCKWEED 



THE rockweeds are said to make up about one-half 

 of our seaweeds. They are of different kinds. Three 

 are found on our Atlantic coast, and one is common 

 on the Pacific coast. 



The plants are large, tough, and leathery. When 

 fresh, they have a distinct olive-green color, but they 

 become almost black when dry. They grow in thick 

 bunches, attached to the rocks by cone-shaped disks 

 or holdfasts. When the tide goes out they hang from 

 the rocks like long fringe. When it rises again, they 

 float and sway in the water like huge bouquets. Some- 

 times the spore cases are scattered over the entire 

 frond. In other plants they are found at the ends 

 of the branches. 



The rockweed that is the most common is called 



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